Ion implants introduce desired dopants into selected regions of a transistor on a semiconductor wafer. A platen, such as, for example, an electrostatic platen, supports the semiconductor wafer during ion implant. The electrostatic platen may be configured with an internal heater to heat the platen and hence the semiconductor wafer to temperatures greater than 150° C. for hot ion implants. Current platens having an internal heater may suffer from reliability concerns, especially at hotter temperatures exceeding 400° C.
Next generation three dimensional transistors, such as finFETs have structures such as fins, which can be doped with desired dopants from an ion implanter. A challenge has been the number of defects present after a subsequent annealing step of the fin. For instance, doping the fins at room temperature has been shown to fully amorphize the entire fin. Higher temperature implants have also been attempted, which may have suboptimal results.
Accordingly, there is a need in the art for new and improved methods of defect control.